Flow-cytometric immunophenotyping of acute leukaemia

: A wide panel of commercially available monoclonal antibodies (Mo.Abs.) has substantially improved immunological distinguishing of various types of acute leukaemias (AL), whereas the flow-cytometric approach allows a more objective and sensitive cell-marker analysis; combined with high numbers of cells analyzed, it yields data of high statistical significance. In addition, multiparameter analysis offers the possibility of studying heterogenous cell populations. Both technical advancements were used to study the expression of leukocyte differentiation antigens in 90 adult patients with AL. With the panel of Mo.Abs. used, the diagnosis was unequivocally established in 90% of cases; four of them (4.4% of the total) expressed unusual (mixed) phenotype. When combined with cytological/cytochemical data, the diagnosis was established in 95.6% of cases, whereas 4.4% of all cases remained unclassified.